in this particular case "We need to be able to capture 60 MHz SPI."

For something cheap and capable you could try building rp2350 based https://github.com/gusmanb/logicanalyzer, goes up to 400Ms/s. Its just a Pico1/2 with a level shifter board

"This is an affordable logic analyzer capable of reaching up to 400Mhz of sampling speed. The analyzer uses a Pico/Pico2 as its core. The analyzer offers 24 channels but can be chained up to 5 devices allowing the sampling of up to 120 channels at once."

I havent played with their software yet, but I have a ton of experience with pulseview and while its feature rich it is sluggish and not suited for high speed big volume acquisitions (especially the dreadfully Python 3.4 plugins and Im saying this as an author of one of the plugins) so anything written even half competently might be better.